In recent years, in magnetic recording apparatuses typified by a HDD (Hard Disk Drive), since the high recording resolution is obtained, perpendicular magnetic recording type have been put into practical use which are comprised of perpendicular two-layer media and single-pole head. Further, as measures for enhancing the in-plane recording density, techniques have been developed to make the magnetic layer bearing recording finer. In the techniques, heat stability of magnetic particles deteriorates due to finer particles, and faced is the so-called thermal fluctuation problem such as deterioration and loss of recorded information. To solve the problem, it has been carried out to provide the magnetic fine-particle structure with increased heat stability using an exchange-coupling type medium that magnetically couples magnetic particles to magnetically stabilize. For example, in CGC media, granular having a fine-particle structure is provided with an exchange coupling layer, and mutually separated magnetic particles are exchange-coupled via the exchange coupling layer (Patent Document 1).    Patent Document 1: U.S. Pat. No. 6,468,670